Driver Jeff Mosing announced this week that he will be unable to compete in the remaining two events of the IMSA Continental Tire SportsCar Challenge and Porsche GT3 Cup USA by Yokohama this year.

Mosing had been dealing with tremendous back pain since an incident in a GT3 Cup race at Watkins Glen in early July, but initial x-rays did not yield any results. Follow-up tests revealed that the resident of Austin, Texas has an L2 compression fracture in his lower back.

The announcement is a devastating blow for Mosing and co-driver Eric Foss, who currently sit atop the Continental Tire Challenge Street Tuner (ST) championship standings with a 22-point lead in their No. 56 Murillo Racing Porsche Cayman. Mosing’s withdrawal will remove him from championship contention, but the team’s results over the next two races could keep Foss in first place as a stand-alone champion.

Unfortunately, Mosing is no stranger to losing a championship due to injury. In 2014, he was forced to withdraw from the third Continental Tire Challenge race of the season at Mazda Raceway Laguna Seca due to back pain. However, he rejoined Foss the following race and the duo drove to one win and three additional podiums before the season’s end, which crowned Foss as the ST champion.

“Upon hearing the news from my doctor, I was devastated,” said Mosing. “This certainly cannot be happening to me again. Another back injury will prevent me from winning another championship in the IMSA Continental Sports Car Challenge. I reflected on it for a couple of days and decided the best thing to do is to focus on the positives.

“Our Murillo Racing team has gotten better at everything they do year after year, and that’s the true reason that I have even had chances at winning a championship. My co-driver, Eric Foss, has a lot to do with it too, as through the years driving with him and having him for a coach has taken years off my learning curve. Yeah, I won’t go down in the record books, again, if the team stays in the lead, but in my heart I battle hard like a champion, and my passion for doing the best that I personally can will continue to shine through my performance on track.”

“Jeff not being able to drive at this point in the season is heartbreaking,” said Foss. “He has done a phenomenal job all season, especially these last couple races while trying to endure a great deal of pain. I’m hoping we can win a team championship for him and that he will return even stronger for next season.”

Mazda Raceway Laguna Seca hosts the Continental Tire Challenge on Sept. 23, the second of two four-hour endurance races on the schedule. The series concludes its season at Road Atlanta on Oct. 6.

While Mosing was no longer in championship contention for the GT3 Cup USA championship after missing both races at Watkins Glen and VIR, the series continues at Sonoma this weekend and Road Atlanta for the season finale.